Abstract:

A stirring device (1) capable of correctly detecting abnormality in a
stirring process and preventing liquid which has not been stirred in a
normal process from being used in an analyzing process, and an analyzer
are provided. The stirring device (1) according to the present invention
includes a nozzle (2), a syringe (14), and an abnormality detecting
section (35) for determining whether or not a stirring process has been
performed in a normal manner on liquid, which is a stirring subject, in a
stirring container (23), on the basis of the amount of deviation between
a suction pressure waveform indicating a suction pressure change measured
by a pressure measuring section (6), and a suction pressure waveform
pre-obtained during normal stirring.

Claims:

1. A stirring device for repeating suction and discharge of liquid in a
container to stir the liquid, comprising:a nozzle for sucking or
discharging the liquid;a pressure generating section for generating
pressure necessary for the nozzle to suck or discharge the liquid;a
pressure measuring section for measuring pressure generated by the
pressure generating section and applied to the nozzle; anda determining
section for determining whether or not a stirring process has been
performed on the liquid in a normal manner, on the basis of an amount of
deviation between a suction pressure waveform indicating a suction
pressure change measured by the pressure measuring section, and a suction
pressure waveform pre-obtained during normal stirring.

2. The stirring device according to claim 1, wherein the determining
section determines that the stirring process has been performed on the
liquid in a normal manner when an integrated value of suction pressure
measurement values within a predetermined period of time of the suction
pressure waveform measured by the pressure measuring section is within a
first tolerance range, which is set on the basis of an integrated value
of pressure measurement values within the predetermined period of time of
the suction pressure waveform pre-obtained during normal stirring; and
determines that the stirring process has not been performed on the liquid
in a normal manner when the integrated value of the suction pressure
measurement values measured by the pressure measuring section has
deviated out of the first tolerance range.

3. The stirring device according to claim 2, wherein the determining
section determines that the stirring process has not been performed on
the liquid in a normal manner due to an insufficient liquid amount or the
nozzle not reaching a liquid surface, when the integrated value of the
suction pressure measurement values measured by the pressure measuring
section is more than an upper limit of the first tolerance range; and
determines that the stirring process has not been performed on the liquid
in a normal manner due to clogging in the nozzle, when the integrated
value of the suction pressure measurement values measured by the pressure
measuring section is less than a lower limit of the first tolerance
range.

4. A stirring device for repeating suction and discharge of liquid in a
container to stir the liquid, comprising:a nozzle for sucking or
discharging the liquid;a pressure generating section for generating
pressure necessary for the nozzle to suck or discharge the liquid;a
pressure measuring section for measuring pressure generated by the
pressure generating section and applied to the nozzle; anda determining
section for determining whether or not a stirring process has been
performed on the liquid in a normal manner, on the basis of an amount of
deviation between a discharge pressure waveform indicating a discharge
pressure change measured by the pressure measuring section, and a
discharge pressure waveform pre-obtained during normal stirring.

5. The stirring device according to claim 4, wherein the determining
section determines that the stirring process has been performed on the
liquid in a normal manner when an integrated value of discharge pressure
measurement values within a predetermined period of time of the discharge
pressure waveform measured by the pressure measuring section is within a
second tolerance range, which is set on the basis of an integrated value
of pressure measurement values within the predetermined period of time of
the discharge pressure waveform pre-obtained during normal stirring; and
determines that the stirring process has not been performed on the liquid
in a normal manner when the integrated value of the discharge pressure
measurement values measured by the pressure measuring section has
deviated out of the second tolerance range.

6. The stirring device according to claim 5, wherein the determining
section determines that the stirring process has not been performed on
the liquid in a normal manner due to clogging in the nozzle, when the
integrated value of the discharge pressure measurement values measured by
the pressure measuring section is more than an upper limit of the second
tolerance range; and determines that the stirring process has not been
performed on the liquid in a normal manner due to an insufficient liquid
amount or the nozzle not reaching a liquid surface, when the integrated
value of the discharge pressure measurement values measured by the
pressure measuring section is less than a lower limit of the second
tolerance range.

7. A stirring device for repeating suction and discharge of liquid in a
container to stir the liquid, comprising:a nozzle for sucking or
discharging the liquid;a pressure generating section for generating
pressure necessary for the nozzle to suck or discharge the liquid;a
pressure measuring section for measuring pressure generated by the
pressure generating section and applied to the nozzle; anda determining
section for determining whether or not a stirring process has been
performed on the liquid in a normal manner, on the basis of an amount of
deviation between a suction pressure waveform indicating a suction
pressure change measured by the pressure measuring section, and a suction
pressure waveform pre-obtained during normal stirring as well as an
amount of deviation between a discharge pressure waveform indicating a
discharge pressure change measured by the pressure measuring section, and
a discharge pressure waveform pre-obtained during normal stirring.

8. The stirring device according to claim 7, wherein the determining
section determines that the stirring process has been performed on the
liquid in a normal manner when an integrated value of suction pressure
measurement values within a predetermined period of time of the suction
pressure waveform measured by the pressure measuring section is within a
first tolerance range, which is set on the basis of an integrated value
of pressure measurement values within the predetermined period of time of
the suction pressure waveform pre-obtained during normal stirring, and
when an integrated value of discharge pressure measurement values within
a predetermined period of time of the discharge pressure waveform
measured by the pressure measuring section is within a second tolerance
range, which is set on the basis of an integrated value of pressure
measurement values within the predetermined period of time of the
discharge pressure waveform pre-obtained during normal stirring; and
determines that the stirring process has not been performed on the liquid
in a normal manner when the integrated value of the suction pressure
measurement values measured by the pressure measuring section has
deviated out of the first tolerance range and/or when the integrated
value of the discharge pressure measurement values measured by the
pressure measuring section has deviated out of the second tolerance
range.

9. The stirring device according to claim 8, wherein the determining
section determines that the stirring process has not been performed on
the liquid in a normal manner due to an insufficient liquid amount, the
nozzle not reaching a liquid surface, clogging in the nozzle or the
nozzle contacting a bottom surface of the container, in accordance with
each combination of: when the integrated value of the suction pressure
measurement values measured by the pressure measuring section is more
than the upper limit of the first tolerance range; or when the integrated
value of the suction pressure measurement values measured by the pressure
measuring section is less than the lower limit of the first tolerance
range; as well as when the integrated value of the discharge pressure
measurement values measured by the pressure measuring section is more
than the upper limit of the second tolerance range; or when the
integrated value of the discharge pressure measurement values measured by
the pressure measuring section is less than the lower limit of the second
tolerance range.

10. The stirring device according to claim 2, wherein the first tolerance
range is set on the basis of the integrated value of pressure measurement
values within the predetermined period of time of the suction pressure
waveform pre-obtained during normal stirring, and dispensing accuracy of
a dispensing device for dispensing the liquid stirred by the stirring
device.

11. The stirring device according to claim 5, wherein the second tolerance
range is set on the basis of the integrated value of pressure measurement
values within the predetermined period of time of the discharge pressure
waveform pre-obtained during normal stirring, and dispensing accuracy of
a dispensing device for dispensing the liquid stirred by the stirring
device.

12. The stirring device according to claim 2, wherein:the pressure
measuring section measures pressure applied to the nozzle for each
suction process at the nozzle; andthe determining section calculates an
average value of integrated values of suction pressure measurement values
at suction processes measured by the pressure measuring section, and
compares the calculated average value of the integrated values with the
first tolerance range to determine whether or not the stirring process
has been performed on the liquid in a normal manner.

13. The stirring device according to claim 5, wherein:the pressure
measuring section measures pressure applied to the nozzle for each
discharge process at the nozzle; andthe determining section calculates an
average value of integrated values of discharge pressure measurement
values at discharge processes measured by the pressure measuring section,
and compares the calculated average value of the integrated values with
the second tolerance range to determine whether or not the stirring
process has been performed on the liquid in a normal manner.

14. The stirring device according to claim 2 wherein the predetermined
period of time is a period of time when a pressure waveform shape
measured by the pressure measuring section is stabilized.

15. An analyzer comprising the stirring device according to claim 1.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This application is a continuation of PCT international application
Ser. No. PCT/JP2009/053086 filed on Feb. 20, 2009 which designates the
United States, incorporated herein by reference, and which claims the
benefit of priority from Japanese Patent Application No. 2008-040177,
filed on Feb. 21, 2008, incorporated herein by reference.

TECHNICAL FIELD

[0002]The present invention relates to a stirring device for repeatedly
sucking and discharging liquid in a container to stir the liquid, and an
analyzer.

BACKGROUND ART

[0003]Analyzers for analyzing blood and bodily fluids are conventionally
provided with a dispenser for dispensing a sample or a reagent into a
reaction tube, the dispenser having a nozzle for sucking or discharging
liquid using pressure transmitted from a syringe. In order to detect
abnormal liquid suction of such a dispenser, a detection method is
proposed for measuring pressure applied to a nozzle and comparing the
rate of change in a measured value of the pressure with a predetermined
threshold value to detect nozzle clogging (see Japanese Laid-Open
Publication No. 2000-46846, for example).

DISCLOSURE OF THE INVENTION

[0004]In an analyzer for analyzing blood and bodily fluids, a stirring
device is used for repeatedly sucking and discharging liquid in a
container to stir the liquid in the container. Such a stirring device is
used, for example, as a pretreatment device for diluting a sample, such
as a whole blood sample, with a diluent, and as a stirring mechanism for
stirring liquid and a reagent in a reaction tube to accelerate the
reaction. In addition, in order to increase the analyzing accuracy of the
analyzer, it is necessary to perform a stirring process appropriately by
the pretreatment device and the stirring mechanism. The reason is as
follows. If a sample and a diluent are not stirred sufficiently in a
container in a pretreatment device, the diluted sample cannot be
dispensed accurately. Alternatively, if a sample and a reagent are not
stirred sufficiently in a reaction tube in a stirring mechanism within an
analyzer, the reaction will not progress appropriately between the sample
and the reagent. Thus, in order to increase the analyzing accuracy in
such an analyzer, it is necessary to detect whether or not a stirring
process is performed in a normal manner in a stirring device.

[0005]In a conventional nozzle clogging detecting method, however,
clogging can be detected only during liquid suction. As a result of this,
in the conventional nozzle clogging detecting method, it is not possible
to detect all the abnormalities in a stirring device, and further, it is
not possible to detect either abnormal liquid suction due to a cause
except for clogging at liquid suction, or abnormal liquid discharge. As
such, since it has not been possible to accurately detect abnormal
stirring of a stirring device, using the conventional nozzle clogging
detecting method, there have been cases where samples which are not
sufficiently diluted and reaction liquids which are not sufficiently
accelerated for reaction are used in analyzing processes.

[0006]The present invention is intended to solve the defect of the
conventional technique described above. The objective of the present
invention is to provide: a stirring device capable of accurately
detecting an abnormal stirring process and preventing liquid, which has
not been stirred in a normal manner, from being used in an analyzing
process; and an analyzer.

[0007]A stirring device according to the present invention for repeating
suction and discharge of liquid in a container to stir the liquid
includes: a nozzle for sucking or discharging the liquid; a pressure
generating section for generating pressure necessary for the nozzle to
suck or discharge the liquid; a pressure measuring section for measuring
pressure generated by the pressure generating section and applied to the
nozzle; and a determining section for determining whether or not a
stirring process has been performed on the liquid in a normal manner, on
the basis of an amount of deviation between a suction pressure waveform
indicating a suction pressure change measured by the pressure measuring
section, and a suction pressure waveform pre-obtained during normal
stirring, thereby achieving the objective described above.

[0008]Further, in the stirring device according to the present invention,
the determining section determines that the stirring process has been
performed on the liquid in a normal manner when an integrated value of
suction pressure measurement values within a predetermined period of time
of the suction pressure waveform measured by the pressure measuring
section is within a first tolerance range, which is set on the basis of
an integrated value of pressure measurement values within the
predetermined period of time of the suction pressure waveform
pre-obtained during normal stirring; and determines that the stirring
process has not been performed on the liquid in a normal manner when the
integrated value of the suction pressure measurement values measured by
the pressure measuring section has deviated out of the first tolerance
range.

[0009]Still further, in the stirring device according to the present
invention, the determining section determines that the stirring process
has not been performed on the liquid in a normal manner due to an
insufficient liquid amount or the nozzle not reaching a liquid surface,
when the integrated value of the suction pressure measurement values
measured by the pressure measuring section is more than an upper limit of
the first tolerance range; and determines that the stirring process has
not been performed on the liquid in a normal manner due to clogging in
the nozzle, when the integrated value of the suction pressure measurement
values measured by the pressure measuring section is less than a lower
limit of the first tolerance range.

[0010]Still further, in the stirring device according to the present
invention, a stirring device for repeating suction and discharge of
liquid in a container to stir the liquid includes: a nozzle for sucking
or discharging the liquid; a pressure generating section for generating
pressure necessary for the nozzle to suck or discharge the liquid; a
pressure measuring section for measuring pressure generated by the
pressure generating section and applied to the nozzle; and a determining
section for determining whether or not a stirring process has been
performed on the liquid in a normal manner, on the basis of an amount of
deviation between a discharge pressure waveform indicating a discharge
pressure change measured by the pressure measuring section, and a
discharge pressure waveform pre-obtained during normal stirring.

[0011]Still further, in the stirring device according to the present
invention, the determining section determines that the stirring process
has been performed on the liquid in a normal manner when an integrated
value of discharge pressure measurement values within a predetermined
period of time of the discharge pressure waveform measured by the
pressure measuring section is within a second tolerance range, which is
set on the basis of an integrated value of pressure measurement values
within the predetermined period of time of the discharge pressure
waveform pre-obtained during normal stirring; and determines that the
stirring process has not been performed on the liquid in a normal manner
when the integrated value of the discharge pressure measurement values
measured by the pressure measuring section has deviated out of the second
tolerance range.

[0012]Still further, in the stirring device according to the present
invention, the determining section determines that the stirring process
has not been performed on the liquid in a normal manner due to clogging
in the nozzle, when the integrated value of the discharge pressure
measurement values measured by the pressure measuring section is more
than an upper limit of the second tolerance range; and determines that
the stirring process has not been performed on the liquid in a normal
manner due to an insufficient liquid amount or the nozzle not reaching a
liquid surface, when the integrated value of the discharge pressure
measurement values measured by the pressure measuring section is less
than a lower limit of the second tolerance range.

[0013]Still further, in the stirring device according to the present
invention, a stirring device for repeating suction and discharge of
liquid in a container to stir the liquid includes: a nozzle for sucking
or discharging the liquid; a pressure generating section for generating
pressure necessary for the nozzle to suck or discharge the liquid; a
pressure measuring section for measuring pressure generated by the
pressure generating section and applied to the nozzle; and a determining
section for determining whether or not a stirring process has been
performed on the liquid in a normal manner, on the basis of an amount of
deviation between a suction pressure waveform indicating a suction
pressure change measured by the pressure measuring section, and a suction
pressure waveform pre-obtained during normal stirring as well as an
amount of deviation between a discharge pressure waveform indicating a
discharge pressure change measured by the pressure measuring section, and
a discharge pressure waveform pre-obtained during normal stirring.

[0014]Still further, in the stirring device according to the present
invention, the determining section determines that the stirring process
has been performed on the liquid in a normal manner when an integrated
value of suction pressure measurement values within a predetermined
period of time of the suction pressure waveform measured by the pressure
measuring section is within a first tolerance range, which is set on the
basis of an integrated value of pressure measurement values within the
predetermined period of time of the suction pressure waveform
pre-obtained during normal stirring, and when an integrated value of
discharge pressure measurement values within a predetermined period of
time of the discharge pressure waveform measured by the pressure
measuring section is within a second tolerance range, which is set on the
basis of an integrated value of pressure measurement values within the
predetermined period of time of the discharge pressure waveform
pre-obtained during normal stirring; and determines that the stirring
process has not been performed on the liquid in a normal manner when the
integrated value of the suction pressure measurement values measured by
the pressure measuring section has deviated out of the first tolerance
range and/or when the integrated value of the discharge pressure
measurement values measured by the pressure measuring section has
deviated out of the second tolerance range.

[0015]Still further, in the stirring device according to the present
invention, the determining section determines that the stirring process
has not been performed on the liquid in a normal manner due to an
insufficient liquid amount, the nozzle not reaching a liquid surface,
clogging in the nozzle or the nozzle contacting a bottom surface of the
container, in accordance with each combination of: when the integrated
value of the suction pressure measurement values measured by the pressure
measuring section is more than the upper limit of the first tolerance
range; or when the integrated value of the suction pressure measurement
values measured by the pressure measuring section is less than the lower
limit of the first tolerance range; as well as when the integrated value
of the discharge pressure measurement values measured by the pressure
measuring section is more than the upper limit of the second tolerance
range; or when the integrated value of the discharge pressure measurement
values measured by the pressure measuring section is less than the lower
limit of the second tolerance range.

[0016]Still further, in the stirring device according to the present
invention, the first tolerance range is set on the basis of the
integrated value of pressure measurement values within the predetermined
period of time of the suction pressure waveform pre-obtained during
normal stirring, and dispensing accuracy of a dispensing device for
dispensing the liquid stirred by the stirring device.

[0017]Still further, in the stirring device according to the present
invention, the second tolerance range is set on the basis of the
integrated value of pressure measurement values within the predetermined
period of time of the discharge pressure waveform pre-obtained during
normal stirring, and dispensing accuracy of a dispensing device for
dispensing the liquid stirred by the stirring device.

[0018]Still further, in the stirring device according to the present
invention, the pressure measuring section measures pressure applied to
the nozzle for each suction process at the nozzle, and the determining
section calculates an average value of integrated values of suction
pressure measurement values at suction processes measured by the pressure
measuring section, and compares the calculated average value of the
integrated values with the first tolerance range to determine whether or
not the stirring process has been performed on the liquid in a normal
manner.

[0019]Still further, in the stirring device according to the present
invention, the pressure measuring section measures pressure applied to
the nozzle for each discharge process at the nozzle, and the determining
section calculates an average value of integrated values of discharge
pressure measurement values at discharge processes measured by the
pressure measuring section, and compares the calculated average value of
the integrated values with the second tolerance range to determine
whether or not the stirring process has been performed on the liquid in a
normal manner.

[0020]Still further, in the stirring device according to the present
invention, the predetermined period of time is a period of time when a
pressure waveform shape measured by the pressure measuring section is
stabilized.

[0021]Still further, an analyzer according to the present invention
includes any one of the above-described stirring device according to the
present invention.

[0022]According to the present invention, in a stirring device for
repeating suction and discharge of liquid in a container to stir the
liquid, it is determined whether or not a stirring process has been
performed in a normal manner on liquid in a container, which is a
stirring subject, on the basis of at least one of the amount of deviation
between a suction pressure waveform, indicating a measured suction
pressure change, and a suction pressure waveform pre-obtained during
normal stirring, or the amount of deviation between a discharge pressure
waveform, indicating a discharge pressure change measured by a pressure
measuring section, and a discharge pressure waveform pre-obtained during
normal stirring. Thereby, it is possible to prevent liquid, which has not
been stirred in a normal manner, from being used in an analyzing process.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 is a diagram schematically illustrating a structure of a
stirring device according to Embodiment 1.

[0024]FIG. 2 is a diagram illustrating time dependence between suction
pressure of normal stirring and suction pressure of abnormal stirring.

[0025]FIG. 3 is a diagram illustrating time dependence between suction
pressure of normal stirring and suction pressure of abnormal stirring.

[0026]FIG. 4 is a diagram describing an abnormality determining process of
a stirring process of the stirring device illustrated in FIG. 1.

[0027]FIG. 5 is a flowchart illustrating process steps of a stirring
process of the stirring device illustrated in FIG. 1.

[0102]Hereinafter, embodiments of the present invention will be described,
with reference to accompanying figures, with an example of a stirring
device functioning as a pretreatment device of an analyzer, for diluting
a sample, such as blood or urine, and a diluent. It is noted that the
present invention is not limited to the embodiments. It is also note that
corresponding portions of the figures are given the same reference
numerals.

Embodiment 1

[0103]First, Embodiment 1 will be described. FIG. 1 is a diagram
schematically illustrating a structure of a stirring device according to
Embodiment 1. A stirring device 1 illustrated in FIG. 1 includes: a
tubular nozzle 2 for sucking and discharging a liquid Sb in a stirring
container 23, the liquid being a stirring subject; a nozzle transferring
section 3 for transferring the nozzle 2 by performing raising and
lowering operations on the nozzle 2 in a vertical direction and a
rotating operation on the nozzle 2 in a horizontal direction; a syringe 4
for performing sucking and discharging operations of a cleaning liquid
Wa, functioning as a pressure transmitting medium for transmitting
pressure to the nozzle 2; a tube 5 for connecting the nozzle 2 and the
syringe 4 to create a flowing pathway of the cleaning liquid Wa; and a
pressure measuring section 6 for detecting pressure applied to the nozzle
2. The cleaning liquid Wa is an incompressible fluid, such as ion
exchanged water or distilled water.

[0104]The nozzle 2, nozzle transferring section 3, syringe 4 and tube 5
repeat sucking and discharging of a sample in the stirring container 23,
the sample being the liquid of a stirring subject, and a diluent to stir
the liquid in the stirring container 23, and also dispense a
predetermined amount of a sample Sa from a container 22, in which the
sample Sa is contained, into the stirring container 23, where the sample
Sa includes a whole blood sample, urine or the like, and is a diluting
subject.

[0105]The stirring device 1 further includes: a tubular nozzle 12 for
injecting a diluent La into the stirring container 23; a nozzle
transferring section (not shown) for transferring the nozzle 12 by
performing raising and lowering operations on the nozzle 12 in a vertical
direction and a rotating operation on the nozzle 2 in a horizontal
direction; a syringe 14 for performing sucking and discharging operations
of the diluent La; and a tube 15 for connecting the nozzle 12 and the
syringe 14 to create a flowing pathway of the diluent La. The diluent La
is ion exchanged water or the like. The nozzle 12, syringe 14 and tube 15
dispense a predetermined amount of the diluent La for diluting sample Sa,
from a diluent tank 21 into the stirring container 23.

[0106]The syringe 4 includes a cylinder 4a and a piston 4b, and the piston
4b slides inside the cylinder 4a by a piston driving section 7 in
vertical upward and downward directions in FIG. 1, thereby generating
pressure to be transmitted to the nozzle 2 via the cleaning liquid Wa.
The syringe 4 achieves part of functions of a pressure generating section
for generating pressure necessary for the nozzle 2 to suck or discharge
the liquid inside the stirring container 23. The syringe 4 is also
connected to a tube 8, other than the tube 5. The other end of the tube 8
reaches a cleaning liquid tank 11 which contains the cleaning liquid Wa.
In addition, the tube 8 is provided with an electromagnetic valve 9 for
adjusting a flow rate of the cleaning liquid Wa and a pump 10 for
performing sucking and discharging operations of the cleaning liquid Wa.
When the electromagnetic valve 9 is opened, the cleaning liquid Wa sucked
up by the pump 10 is supplied into the cylinder 4a.

[0107]The pressure measuring section 6 includes: a pressure sensor 61,
connected with the tube 5, for detecting a pressure change of the
cleaning liquid Wa filling the tube 5 to convert it into an electric
signal; and a signal processing circuit 62 for performing signal
processing, such as amplification and A/D conversion, to the electric
signal output from the pressure sensor 61. Thereby the pressure measuring
section 6 measures pressure applied to the nozzle 2. It is more
preferable to dispose the pressure measuring section 6 near the nozzle 2;
however, depending on conditions such as the sensitivity of the pressure
sensor 61, the pressure measuring section 6 may be disposed in a middle
portion of the nozzle 2 and the syringe 4, or may be disposed near the
syringe 4.

[0108]In addition, the syringe 14 includes a cylinder 14a and a piston
14b. The syringe 14 is also connected to a tube 18, other than the tube
15. The other end of the tube 18 reaches a diluent tank 21 which contains
the diluent La. In addition, the tube 18 is provided with an
electromagnetic valve 19 for adjusting a flow rate of the diluent La and
a pump 20 for performing sucking and discharging operations of the
diluent La. When the electromagnetic valve 19 is opened, the diluent La
sucked up by the pump 20 is supplied into the cylinder 14a. In addition,
the piston 14b slides inside the cylinder 14a by a piston driving section
17 in vertical upward and downward directions in FIG. 1, thereby a
predetermined amount of the diluent La from the syringe 14 is injected
through the nozzle 12 into the stirring container 23.

[0109]The stirring device 1 further includes: a controlling section 30 for
controlling a motion process of elements constituting the stirring device
1; an input section 34 for inputting various information; an abnormality
detecting section 35 for detecting an abnormality in a stirring process
in the stirring device 1; a storing section 36 for storing various
information used for an abnormality detecting process by the abnormality
detecting section 35; and an output section 37 for outputting various
information.

[0110]The abnormality detecting section 35 detects whether or not a
stirring process is performed in a normal manner on the liquid Sb in the
stirring container 23, on the basis of the amount of deviation between a
suction pressure waveform pre-obtained during normal stirring and a
suction pressure waveform, measured by the pressure measuring section 6,
indicating a suction pressure change.

[0111]With reference to FIG. 2, a suction pressure waveform of normal
stirring and a suction pressure waveform of abnormal stirring will be
specifically described. FIG. 2 is a diagram illustrating time dependence
between suction pressure of normal stirring and suction pressure of
abnormal stirring. In FIG. 2, the number 0 in the axis of ordinates
approximately represents atmospheric pressure. A waveform Ws0 in FIG. 2
represents the suction pressure waveform of normal stirring. Further, a
waveform Ws1 represents a suction pressure waveform of abnormal stirring
resulting from the occurrence of clogging by fibrin or the like in the
nozzle 2. Still further, a waveform Ws2 represents a suction pressure
waveform of abnormal stirring resulting from the insufficient amount of
liquid of a stirring subject, or the nozzle 2 not reaching a liquid
surface. In addition, the piston 4b starts sliding in the downward
direction at a time Tss to start the suction of the liquid. Subsequently,
the piston 4b stops sliding in the downward direction at a time Tse to
end the suction of the liquid.

[0112]As represented by the waveform Ws0 in FIG. 2, during normal
stirring, the pressure waveform is represented with the amplitude
becoming gradually smaller with the elapse of suction. On the contrary,
when the nozzle 2 is clogged as represented by the waveform Ws1 of
abnormal stirring in FIG. 2 resulting from the occurrence of clogging in
the nozzle 2, the suction pressure is rapidly decreased immediately after
the start of the suction, and a saturated condition continues at a value
with high negative pressure (lower than atmospheric pressure but the
absolute value is high). In addition, when the amount of liquid of a
stirring subject is not sufficient as represented by a waveform Ws2 of
abnormal stirring resulting from the insufficient amount of the liquid or
the nozzle 2 not reaching a liquid surface, the suction pressure value is
indicated by a value with a lower negative pressure (with a smaller
absolute value) compared to the case of normal stirring because the
nozzle 2 cannot suck a predetermined amount of the liquid.

[0113]Next, FIG. 3 illustrates each of the waveforms within a
predetermined period of time Ts, from a time Ts1 to a time Ts2, when each
of the pressure waveforms is stabilized. As illustrated in FIG. 3, the
waveform Ws1 of abnormal stirring resulting from the occurrence of
clogging in the nozzle 2 continues to represent a value with constantly
higher negative pressure than the waveform Ws0 of normal stirring. As a
result, an integrated value As1 with respect to the waveform Ws1,
represented by an arrow Y11, is remarkably smaller (where the absolute
value becomes greater) than an integrated value As0 with respect to the
waveform Ws0 of normal stirring, represented by an arrow Y10. Thus, when
the nozzle 2 is clogged, the integrated value As1 of suction pressure
values during the predetermined period of time Ts constantly becomes
smaller than the integrated value As0 of normal stirring.

[0114]As described above, in the stirring device 1, it is determined
whether or not there is an abnormality in the stirring process by making
use of the fact that when the nozzle 2 is clogged, the integrated value
of suction pressure values during the predetermined period of time Ts
becomes remarkably smaller than the integrated value As0 with respect to
the waveform Ws0 of normal stirring.

[0115]More specifically, the stirring device 1 sets a predetermined
threshold value As01 as represented by an arrow Y13 on the basis of the
integrated value As0 of normal stirring and the integrated value As1 of
abnormal stirring resulting from the occurrence of clogging in the nozzle
2, and determines abnormal stirring due to the occurrence of clogging in
the nozzle 2, using the threshold value As01. The threshold value As01 is
set on the basis of the integrated value of pressure measurement values
within the predetermined period of time Ts of the suction pressure
waveform pre-obtained during normal stirring. The integrated value of
pressure measurement values during the predetermined period of time Ts of
the pre-obtained suction pressure waveform of normal stirring, is
obtained as follows: in a normal condition, a stirring process is
performed for a set number of times, and the integrated value of pressure
measurement values during the predetermined period of time Ts is obtained
for each stirring process; and the average of the integrated values is
calculated. In addition, since it is necessary for an accurate amount of
each of a diluent and a stirred sample to be dispensed by the stirring
device 1, the threshold value As01 is determined on the basis of
dispensing accuracy of a dispensing mechanism for dispensing a
predetermined amount of liquid, which is stirred by the stirring device
1, for an analyzing process. For example, the threshold value As01 is a
value obtained by subtracting 20% from the average value of the
integrated values As0 of respective pressure measurement values of normal
stirring.

[0116]Therefore, as illustrated in FIG. 4, when the integrated value of
suction pressure values is less than the threshold value As01 during the
predetermined period of time Ts, during which each pressure waveform is
stabilized, it can be determined that the nozzle 2 is clogged and the
stirring process has not been performed in a normal manner.

[0117]Further, as illustrated in FIG. 3, inmost of the cases, the waveform
Ws2 of abnormal stirring, which is resulting from the insufficient amount
of liquid or the nozzle 2 not reaching the liquid surface, continues to
represent a value with low negative pressure compared to the waveform Ws0
of normal stirring. Therefore, an integrated value As2 with respect to
the waveform Ws2 represented by the arrow Y12 is greater (where the
absolute value is smaller) than the integrated value As0 with respect to
the waveform Ws0 of normal stirring. Thus, in the case where the amount
of liquid of a stirring subject is not sufficient or the nozzle 2 does
not reach the liquid surface, the integrated value As2 of suction
pressure values during the predetermined period of time Ts becomes
greater than the integrated value As0 with respect to the waveform Ws0 of
normal stirring.

[0118]As described above, in the stirring device 1, it is determined
whether or not there is an abnormality in the stirring process by making
use of the fact that when the amount of liquid of a stirring subject is
not sufficient or the nozzle 2 does not reach the liquid surface, the
integrated value of suction pressure values during the predetermined
period of time Ts becomes greater than the integrated value As0 with
respect to the waveform Ws0 of normal stirring. More specifically, the
stirring device 1 sets a predetermined threshold value As02 as
represented by an arrow Y14 on the basis of the integrated value As0 of
normal stirring and the integrated value As2 of abnormal stirring
resulting from the insufficient amount of liquid or the nozzle 2 not
reaching the liquid surface, and determines abnormal stirring due to the
insufficient amount of liquid or the nozzle 2 not reaching the liquid
surface, using the threshold value As02. The threshold value As02 is set
on the basis of the integrated value of pressure measurement values
within the predetermined period of time Ts of the suction pressure
waveform pre-obtained during normal stirring. In addition, since it is
necessary for an accurate amount of each of a diluent and a stirred
sample to be dispensed by the stirring device 1, the threshold value As02
is determined on the basis of dispensing accuracy of a dispensing
mechanism for dispensing a predetermined amount of liquid, which is
stirred by the stirring device 1, for an analyzing process. For example,
the threshold value As02 is a value obtained by adding 20% to the average
value of the integrated values As0 of respective pressure measurement
values of normal stirring.

[0119]Therefore, as illustrated in FIG. 4, when the integrated value of
suction pressure values is more than the threshold value As02 during the
predetermined period of time Ts, during which each pressure waveform is
stabilized, it can be determined that the amount of the liquid is not
sufficient or the nozzle 2 does not reach the liquid surface and the
stirring process has not been performed in a normal manner.

[0120]That is, as illustrated in FIG. 4, when the integrated value of
suction pressure values is within the range from the threshold value As02
to the threshold value As01 during the predetermined period of time Ts,
during which each pressure waveform is stabilized, that is, when the
integrated value is within the range of the upper limit of the threshold
value As02 and the lower limit of the threshold value As01, it can be
determined that the stirring process is performed in a normal manner in
the stirring device 1. In addition, when the integrated value of suction
pressure values is less than the threshold value As01, it can be
determined that the nozzle 2 is clogged and the stirring process has not
been performed in a normal manner. Further, when the integrated value of
suction pressure values is more than the threshold value As02, it can be
determined that the amount of liquid is not sufficient or the nozzle 2
does not reach the liquid surface, resulting in an abnormal stirring
process.

[0121]As described above, in the stirring device 1, the presence of
abnormality in the stirring process and the cause of the abnormal
stirring are determined on the basis of the integrated value As0 of
normal stirring and tolerance between the threshold value As02 and the
threshold value As01, which is set on the basis of dispensing accuracy of
a dispensing device for dispensing a predetermined amount of liquid
stirred by the stirring device 1. In addition, it is noted that the
storing section 36 stores the threshold value As01 and the threshold
value As02.

[0122]Next, the stirring process in the stirring device 1 will be
described with reference to FIG. 5. As illustrated in FIG. 5, in the
stirring device 1, under a transferring process of the nozzle 2 by the
nozzle transferring section 3 and a driving process of the piston 4b by
the piston driving section 7, the nozzle 2 performs a undiluted liquid
dispensing process for dispensing a predetermined amount of the sample
Sa, the undiluted liquid, from the container 22 into the stirring
container 23 (step S1). Next, under a driving process of the piston 14b
by the piston driving section 17, the nozzle 12 performs a diluent
injecting process for injecting a predetermined amount of the diluent La
from the diluent tank 21 into the stirring container 23 (step S2).
Subsequently, the nozzle transferring section 3 performs a nozzle
lowering process for lowering the nozzle 2 into the stirring container 23
(step S3).

[0125]The controlling section 30 determines whether or not the
stirring-subject liquid suction process (step S5) and stirring-subject
liquid discharging process (step S6) are performed for a set number of
times (step S8). If the controlling section 30 determines that the
processes have not been performed for a set number of times (step S8:
No), the process goes back to the step S4 to perform the stirring-subject
liquid suction process (step S5) and stirring-subject liquid discharging
process (step S6) for a set number of times, and the pressure measurement
starting process (step S4), stirring-subject liquid suction process (step
S5) and stirring-subject liquid discharging process (step S6) are
performed.

[0126]On the other hand, if the controlling section 30 determines that the
stirring-subject liquid suction process (step S5) and stirring-subject
liquid discharging process (step S6) have been performed a set number of
times (step S8: Yes), in order to end the stirring process, the nozzle
transferring section 3 performs a nozzle raising process for raising the
nozzle 2 from the stirring container 23 (step S9).

[0127]Next, the abnormality detecting section 35 compares an integrated
value of pressure measurement values of suction, among pressure values
added to the nozzle 2 measured by the pressure measuring section 6, with
each of threshold values stored in the storing section 36 to perform an
abnormal stirring detecting process for detecting the presence of
abnormality in the stirring process and a cause of abnormal stirring
(step S10).

[0128]Next, the controlling section 30 determines whether or not
abnormality in the stirring process is detected by the abnormality
detecting section 35 (step S11). If the controlling section 30 determines
that abnormality is detected in the stirring process by the abnormality
detecting section 35 (step S11: Yes), the controlling section 30 allows
the output section 37 to output the fact that there is abnormality in the
subject stirring process as well as an error message indicating the cause
of the abnormality in the stirring process (step S12). On the other hand,
if the controlling section 30 determines that no abnormality is an
detected in the stirring process by the abnormality detecting section 35
(step S11: No), the controlling section 30 allows the output section 37
to output an message indicating that the subject stirring process has
ended in a normal manner (step S13).

[0129]Next, the abnormal stirring detecting process illustrated in FIG. 5
will be described with reference to FIG. 6. As illustrated in FIG. 6, the
abnormality detecting section 35 obtains suction pressure data, which
represents a pressure measurement value of suction, among pressure
measurement values measured by the pressure measuring section 6 (step
S22). Subsequently, the abnormality detecting section 35 performs a
calculating process for integrating pressure measurement values within
the predetermined period of time Ts for every set of stirring-subject
liquid suction processes performed a set number of times to calculate an
average value Asm of the integrated values (step S24). Next, the
abnormality detecting section 35 obtains threshold values As01 and As02
from the storing section 36 (step S26). The abnormality detecting section
35 detects the presence of an abnormality in the stirring process and a
cause of abnormal stirring by comparing the calculated average value Asm
of the integrated values and the obtained threshold values As01 and As02.

[0130]First, the abnormality detecting section 35 compares the threshold
value As01, which is the upper limit of the above-described tolerance,
and the calculated average value Asm of the integrated values to
determine whether As01>Asm holds (step S28). If the abnormality
detecting section 35 determines that As01>Asm (step S28: Yes), that
is, if the average value Asm of the integrated values of actual suction
pressure measurement values in the nozzle 2 is less than the threshold
value As01 and has deviated out of the tolerance, the threshold value
being the lower limit of the tolerance and being a reference for
determining the occurrence of clogging in the nozzle 2, it is determined
that the subject stirring process has not been performed in a normal
manner due to clogging in the nozzle 2 (step S30).

[0131]On the other hand, if the abnormality detecting section 35
determines that As01>Asm does not hold (step S28: No), that is, if the
average value Asm of the integrated values of actual suction pressure
measurement values in the nozzle 2 is equal to or greater than the
threshold value As01, the threshold value being the lower limit of the
tolerance and being a reference for determining the occurrence of
clogging in the nozzle 2, the abnormality detecting section 35 compares
the threshold value As02, which is the upper limit of the above-described
tolerance, and the calculated average value Asm of the integrated values
to determine whether or not Asm>As02 holds (step S32).

[0132]If the abnormality detecting section 35 determines that Asm>As02
holds (step S32: Yes), that is, if the average value Asm of the
integrated values of actual suction pressure measurement values in the
nozzle 2 is more than the threshold As02 and has deviated out of the
tolerance, the threshold being a reference for determining the occurrence
of the insufficient liquid amount or the nozzle 2 not reaching the liquid
surface and being the upper limit of the tolerance, it is determined that
the subject stirring process has not been performed in a normal manner
due to the insufficient liquid amount or the nozzle 2 not reaching the
liquid surface (step S34). In this case, abnormality in the transfer
controlling of the nozzle transferring section 3 for transferring the
nozzle 2, insufficient dispensing amount of the sample Sa by the nozzle
2, or insufficient injecting amount of the diluent La by the nozzle 12 is
conceivable.

[0133]On the other hand, if the abnormality detecting section 35
determines that Asm>As02 does not hold (step S32: No), since such a
case occurs when the average value Asm of the integrated values of actual
suction pressure measurement values in the nozzle 2 is within a reference
range, it is determined that the stirring process has been performed in a
normal manner (step S36). Subsequently, the abnormality detecting section
35 outputs a detection result (step S38), and ends the abnormal stirring
detecting process.

[0134]As described above, the stirring device 1 according to Embodiment 1
determines whether or not the stirring process has been performed in a
normal manner on liquid of a stirring subject in the container, on the
basis of the amount of deviation between a suction pressure waveform
measured by the pressure measuring section 6 and the suction pressure
waveform pre-obtained during normal stirring. Thereby, it becomes
possible to prevent liquid that is not stirred in a normal manner from
being used in an analyzing process, and reduce the waste of reagents and
analyzing time in the analyzing process.

[0135]In addition, the stirring device 1 determines whether or not the
integrated value of suction pressure measurement values within the
predetermined period of time Ts of the suction pressure waveform measured
by the pressure measuring section 6, is within the tolerance range set on
the basis of the integrated value of pressure measurement values within
the predetermined period of time Ts of the suction pressure waveform
pre-obtained during normal stirring. In other words, the stirring device
1 determines whether there is abnormality in the stirring process using a
value obtained by integrating timewise the amount of deviation from the
suction pressure waveform of normal stirring of the suction pressure
waveform measured by the pressure measuring section 6; and there are a
plurality of pressure measurement values to be integrated. Thereby, a
more reliable determination can be made as to whether or not there is an
abnormality in the stirring process, compared to the case where the
determination is made using the amount of deviation at only one point. In
addition, in the stirring device 1, the abnormality detecting process is
performed on the basis of, not a pressure measurement value within an
unstable state, but an integrated value of pressure measurement values
within a period when the suction pressure waveform is stabilized.
Thereby, it becomes possible to reduce an influence of deviation in
pressure measurement values in an unstable state to perform detecting of
abnormality in a stirring process accurately. Further, in the stirring
device 1, each integrated value of pressure measurement values is
calculated for each plurality of suction processes and the abnormality
detecting process is performed using the average value of the plurality
of integrated values, so that there is a larger number of monitored
points and measured suction pressure values to be averaged, compared to
the case where the determination is made using an integrated value of
pressure measurement values of only one suction process, thereby
performing a reliable determination of whether or not there is an
abnormality in a stirring process.

[0136]Further, according to Embodiment 1, it is possible to detect, not
only the existence of a simple abnormality in a stirring process, but
also the cause of the abnormality in the stirring process. Accordingly, a
maintenance worker of the stirring device 1 can recognize with which
mechanism a cause of abnormality in the stirring process is associated,
thereby handling the abnormality in the stirring process of the stirring
device quickly and accurately.

[0137]Typically, when different liquids of a stirring subject have the
same amount and viscosity, a suction pressure waveform will be
substantially the same every time during a stirring process performed in
a normal manner. Therefore, the stirring device 1 may determine the
existence of abnormal stirring on the basis of each tolerance range in
accordance with each amount and viscosity of liquid to be a stirring
subject. More specifically, the stirring device 1 may perform stirring
processes in advance with different amounts and viscosities of liquid,
and obtain an integrated value of suction pressure values within a
predetermined period of time of a suction pressure waveform in the
stirring processes, and the stirring device 1 may set, on the basis of
respective integrated values or the like, a threshold value As01, which
is the lower limit of a tolerance range, and a threshold value As02,
which is the upper limit of a tolerance range, corresponding to each
amount and each viscosity of liquid.

[0138]In addition, according to Embodiment 1, it is also possible to
provide a threshold value corresponding to each of the insufficient
liquid amount and the nozzle 2 not reaching the liquid surface, to
determine in detail which of the insufficient liquid amount or the nozzle
2 not reaching the liquid surface has caused an abnormal stirring
process.

[0139]FIG. 7 illustrates a waveform Ws0 representing a suction pressure
waveform of normal stirring as well as a waveform Ws21 representing a
suction pressure waveform of abnormal stirring resulting from an
insufficient liquid amount, and a waveform Ws22 representing a suction
pressure waveform of abnormal stirring resulting from the nozzle 2 not
reaching a liquid surface. As represented by the waveform Ws21 in FIG. 7,
each suction pressure value at an insufficient liquid amount indicates a
value with a lower negative pressure compared to the waveform Ws0 at
normal stirring because the amount of sucked liquid is less than a
predetermined amount. Further, as represented by the waveform Ws22 in
FIG. 7, each suction pressure value in the case of the nozzle 2 not
reaching a liquid surface indicates a value with a still lower negative
pressure, compared to the waveform Ws21 in the case of an insufficient
liquid amount, because the liquid cannot be sucked. As described above, a
certain tendency can be recognized in a value distribution of respective
suction pressure values in the case of an insufficient liquid amount and
the case of the nozzle 2 not reaching a liquid surface. In the stirring
device 1, this tendency is used and a threshold value is set, which
allows to distinguish the case of an insufficient liquid amount from the
case of the nozzle 2 not reaching a liquid surface, in addition to the
threshold value As02, which allows to distinguish whether or not it is
normal stirring, to determine which is the cause of the abnormal stirring
process, the insufficient liquid amount or the nozzle 2 not reaching a
liquid surface.

[0140]More specifically, a threshold value As03 may be set, which allows
to distinguish the case of the insufficient liquid amount from the case
of the nozzle 2 not reaching a liquid surface, as represented by an arrow
Y17, on the basis of an average value As21 of integrated values of
suction pressure values within the predetermined period of time Ts in the
waveform Ws21 at an insufficient liquid amount represented by an arrow
Y15, and an average value As22 of integrated values of suction pressure
values within the predetermined period of time Ts in the waveform Ws22 in
the case of the nozzle 2 not reaching a liquid surface represented by an
arrow Y16.

[0141]Therefore, as illustrated in FIG. 8, the abnormality detecting
section 35 determines that a stirring process has not been performed in a
normal manner due to an insufficient liquid amount in a case where an
integrated value of suction pressure values is more than the threshold
value As02 and is equal to or less than the threshold value As03 within a
predetermined period of time Ts, during which pressure waveforms are
stabilized. In addition, the abnormality detecting section 35 determines
that a stirring process has not been performed in a normal manner due to
the nozzle 2 not reaching a liquid surface in a case where an integrated
value of suction pressure values is more than the threshold value As02
and is still more than the threshold value As03 within a predetermined
period of time Ts, during which pressure waveforms are stabilized. As
described above, by further providing the threshold value As03, the
stirring device 1 may determine in detail which is the cause of an
abnormal stirring process, the insufficient liquid amount or the nozzle 2
not reaching a liquid surface.

Embodiment 2

[0142]Next, Embodiment 2 will be described. In Embodiment 2, a case will
be described for detecting abnormality in a stirring process on the basis
of a pressure waveform at liquid discharging in the stirring process.
FIG. 9 is a diagram schematically illustrating a structure of a stirring
device according to Embodiment 2. As illustrated in FIG. 9, a stirring
device 201 according to Embodiment 2 includes an abnormality detecting
section 235 instead of the abnormality detecting section 35 illustrated
in FIG. 1.

[0143]The abnormality detecting section 235 determines whether or not a
stirring process has been performed in a normal manner with respect to
liquid Sb in a stirring container 23, on the basis of the amount of
deviation between a discharge pressure waveform representing a discharge
pressure change measured by a pressure measuring section 6 and a
discharge pressure waveform pre-obtained during normal stirring.

[0144]A discharge pressure waveform of normal stirring and a discharge
pressure waveform of abnormal stirring will be specifically described
with reference to FIG. 10. FIG. 10 is a diagram illustrating time
dependence between a discharge pressure of normal stirring and a
discharge pressure of abnormal stirring. In FIG. 10, a waveform Wg0
represents a discharge pressure waveform at normal stirring; and a
waveform Wg2 represents a discharge pressure waveform of abnormal
stirring resulting from an insufficient amount of liquid of a stirring
subject or a nozzle 2 not reaching a liquid surface. In addition, at a
time Tgs, sliding of a piston 4b starts in an upward direction and liquid
starts to be discharged. Subsequently, at a time Tge, the sliding of the
piston 4b in the upward direction is stopped and the discharge of the
liquid ends.

[0145]As represented by the waveform Wg0 in FIG. 10, during normal
stirring, a pressure waveform is represented with the amplitude becoming
gradually smaller with the elapse of discharge. On the contrary, as
represented by a waveform Wg1 of abnormal stirring in FIG. 10 resulting
from the occurrence of clogging in a nozzle 2, when the nozzle 2 is
clogged, discharge pressure resulting from the clogging and is rapidly
increased immediately after the start of discharging, and a saturated
state with a large value is attained. In addition, if the amount of
liquid of a stirring subject is not sufficient, the nozzle 2 will not be
able to discharge a predetermined amount of liquid and the liquid of a
discharging subject will be in a state where it does not exist in the
nozzle 2 either from the beginning or at midway. Thus, a discharge
pressure value will represent a state with a lower pressure compared to a
normal state.

[0146]Next, FIG. 11 illustrates each waveform during a predetermined
period of time Tg from a time Tg1 to a time Tg2, during which each of
pressure waveforms is stabilized. As illustrated in FIG. 11, the waveform
Wg1 of abnormal stirring resulting from the occurrence of clogging in a
nozzle 2 constantly continues to represent a discharge pressure value
higher than the waveform Wg0 of normal stirring. Therefore, regarding an
integrated value of discharge pressure values during the predetermined
period of time Tg in the case where the nozzle 2 is clogged, an
integrated value Ag1 with respected to the waveform Wg1 represented by an
arrow Y21 is constantly greater than an integrated value Ag0 with
respected to the waveform Wg0 represented by an arrow Y20.

[0147]As described above, in the stirring device 201, it is determined
whether or not there is an abnormality in a stirring process by using the
fact that when the nozzle 2 is clogged, an integrated value of discharge
pressure values during the predetermined period of time Tg is constantly
greater than the integrated value Ag0 with respect to the waveform Wg0 of
normal stirring.

[0148]More specifically, the stirring device 201 sets a predetermined
threshold value Ag01 as represented by an arrow Y23, on the basis of the
integrated value Ag0 of normal stirring and the integrated value Ag1 of
abnormal stirring resulting from the occurrence of clogging in the nozzle
2, and determines abnormal stirring due to the occurrence of clogging in
the nozzle 2, using the threshold value. The threshold value Ag01 is set
on the basis of an integrated value of pressure measurement values within
the predetermined period of time Tg of a discharge pressure waveform
pre-obtained during normal stirring. The integrated value of pressure
measurement values during the predetermined period of time Tg of a
discharge pressure waveform pre-obtained during normal stirring, can be
obtained by performing a stirring process for a set number of times at
normal state, and obtaining an integrated value of pressure measurement
values within the predetermined period of time Tg for each stirring
process to calculate an average value of the integrated values. In
addition, since it is necessary for an accurate amount of a diluent and a
stirred sample to be dispensed by the stirring device 201, the threshold
value Ag01 is set on the basis of dispensing accuracy of a dispensing
device for the dispensing a predetermined amount of liquid, which is
stirred by the stirring device 201, for an analyzing process. For
example, the threshold value Ag01 is a value obtained by adding 20% to
the average value of the integrated values Ag0 of respective pressure
measurement values of normal stirring.

[0149]Therefore, as illustrated in FIG. 12, when the integrated value of
discharge pressure values is more than the threshold value Ag01 during
the predetermined period of time Tg, during which each pressure waveform
is stabilized, it can be determined that the nozzle 2 is clogged and the
stirring process has not been performed in a normal manner.

[0150]In addition, as illustrated in FIG. 11, the waveform Wg2 of abnormal
stirring resulting from an insufficient liquid amount or the nozzle 2 not
reaching a liquid surface, continues to represent a discharge pressure
value lower than the waveform Wg0 of normal stirring in most of the
cases. Therefore, in the case where the amount of liquid of a stirring
subject is not sufficient or the case where the nozzle 2 does not reach a
liquid surface, regarding an integrated value of discharge pressure
values during the predetermined period of time Tg, the integrated value
Ag2 with respect to the waveform Wg2 represented by an arrow Y22 is
smaller than the integrated value Ag0 with respect to the waveform Wg0 of
normal stirring.

[0151]As described above, in the stirring device 201, it is determined
whether there is abnormality in the stirring process by using the fact
that the integrated value of discharge pressure values during the
predetermined period of time Tg is smaller than the integrated value Ag0
with respect to the waveform Wg0 of normal stirring in the case where the
amount of liquid of a stirring subject is not sufficient or the case
where the nozzle 2 does not reach a liquid surface. More specifically,
the stirring device 201 sets a predetermined threshold value Ag02 as
represented by an arrow Y24 on the basis of the integrated value Ag0 of
normal stirring and the integrated value Ag2 of abnormal stirring
resulting from the insufficient amount of liquid or the nozzle 2 not
reaching the liquid surface, and determines abnormal stirring due to the
insufficient amount of liquid or the nozzle 2 not reaching the liquid
surface, using the threshold value Ag02. The threshold value Ag02 is set
on the basis of the integrated value of pressure measurement values
within the predetermined period of time Tg of the discharge pressure
waveform pre-obtained during normal stirring. In addition, since it is
necessary for an accurate amount of each of a diluent and a stirred
sample to be dispensed by the stirring device 201, the threshold value
Ag02 is determined on the basis of dispensing accuracy of a dispensing
device for dispensing a predetermined amount of liquid, which is stirred
by the stirring device 201, for an analyzing process. For example, the
threshold value Ag02 is a value obtained by subtracting 20% from the
average value of the integrated values Ag0 of respective pressure
measurement values of normal stirring.

[0152]Therefore, as illustrated in FIG. 12, when the integrated value of
discharge pressure values is less than the threshold value Ag02 during
the predetermined period of time Tg, during which each pressure waveform
is stabilized, it can be determined that the amount of the liquid is not
sufficient or the nozzle 2 does not reach the liquid surface and the
stirring process has not been performed in a normal manner.

[0153]That is, as illustrated in FIG. 12, when the integrated value of
discharge pressure values is within the range from the threshold value
Ag02 to the threshold value Ag01 during the predetermined period of time
Tg, during which each pressure waveform is stabilized, that is, when the
integrated value is within the range of the upper limit of the threshold
value Ag01 and the lower limit of the threshold value Ag02, it can be
determined that the stirring process is performed in a normal manner in
the stirring device 201. In addition, when the integrated value of
discharge pressure values is more than the threshold value Ag01, it can
be determined that the nozzle 2 is clogged and the stirring process has
not been performed in a normal manner. Further, when the integrated value
of discharge pressure values is less than the threshold value Ag02, it
can be determined that the amount of liquid is not sufficient or the
nozzle 2 does not reach the liquid surface, resulting in an abnormal
stirring process.

[0154]As described above, in the stirring device 201, the presence of an
abnormality in the stirring process and the cause of the abnormal
stirring are determined on the basis of the integrated value Ag0 of
normal stirring and tolerance between the threshold value Ag01 and the
threshold value Ag02, which is set on the basis of the dispensing
accuracy of a dispensing device for dispensing a predetermined amount of
liquid stirred by the stirring device 201. In addition, it is noted that
the storing section 36 stores the threshold value Ag01 and the threshold
value Ag02.

[0155]Next, the stirring process in the stirring device 201 will be
described with reference to FIG. 13. As illustrated in FIG. 13, the
stirring device 201 performs process steps similar to the steps S1 to S9
illustrated in FIG. 5, so as to perform an undiluted solution dispensing
process (step S201), a diluent injecting process (step S202), a nozzle
lowering process (step S203), a pressure measurement starting process
(step S204), a stirring-subject liquid suction process (step S205), a
stirring-subject liquid discharging process (step S206), a pressure
measurement ending process (step S207), a stirring-subject liquid suction
process and stirring-subject liquid discharging process performed for a
set number of times determining process (step S208), and a nozzle raising
process (step S209).

[0156]Next, the abnormality detecting section 235 compares an integrated
value of pressure measurement values at discharge, among pressure values
added to the nozzle 2 measured by the pressure measuring section 6, with
each of threshold values stored in the storing section 36 to perform an
abnormal stirring detecting process for detecting the presence of
abnormality in the stirring process and a cause of abnormal stirring
(step S210).

[0158]Next, the abnormal stirring detecting process illustrated in FIG. 13
will be described with reference to FIG. 14. As illustrated in FIG. 14,
the abnormality detecting section 235 obtains discharge pressure data,
which represents a pressure measurement value at discharge, among
pressure measurement values measured by the pressure measuring section 6
(step S222). Subsequently, the abnormality detecting section 235 performs
a calculating process for integrating pressure measurement values within
the predetermined period of time Tg for every set of stirring-subject
liquid discharging processes performed a set number of times to calculate
an average value Agm of the integrated values (step S224). Next, the
abnormality detecting section 235 obtains threshold values Ag01 and Ag02
from the storing section 36 (step S226). The abnormality detecting
section 235 detects the presence of an abnormality in the stirring
process and a cause of abnormal stirring by comparing the calculated
average value Agm of the integrated values and the obtained threshold
values Ag01 and Ag02.

[0159]First, the abnormality detecting section 235 compares the threshold
value Ag01, which is the upper limit of the above-described tolerance,
and the calculated average value Agm of the integrated values to
determine whether Agm>Ag01 holds (step S228). If the abnormality
detecting section 235 determines that Agm>Ag01 (step S228: Yes), that
is, if the average value Agm of the integrated values of actual discharge
pressure measurement values in the nozzle 2 is more than the threshold
value Ag01 and has deviated out of the tolerance, the threshold value
being the upper limit of the tolerance and being a reference for
determining the occurrence of clogging in the nozzle 2, it is determined
that the subject stirring process has not been performed in a normal
manner due to the clogging in the nozzle 2 (step S230).

[0160]On the other hand, if the abnormality detecting section 235
determines that Agm>Ag01 does not hold (step S228: No), that is, if
the average value Agm of the integrated values of actual discharge
pressure measurement values in the nozzle 2 is equal to or less than the
threshold value Ag01, the threshold value being the upper limit of the
tolerance and being a reference for determining the occurrence of
clogging in the nozzle 2, the abnormality detecting section 235 compares
the threshold value Ag02, which is the lower limit of the above-described
tolerance, and the calculated average value Agm of the integrated values
to determine whether or not Ag02>Agm holds (step S232).

[0161]If the abnormality detecting section 235 determines that Ag02>Agm
holds (step S232: Yes), that is, if the average value Agm of the
integrated values of actual discharge pressure measurement values in the
nozzle 2 is less than the threshold As02 and has deviated out of the
tolerance, the threshold being a reference for determining the occurrence
of the insufficient liquid amount or the nozzle 2 not reaching the liquid
surface and being the lower limit of the tolerance, it is determined that
the subject stirring process has not been performed in a normal manner
due to the insufficient liquid amount or the nozzle 2 not reaching the
liquid surface (step S234). In this case, an abnormality in the transfer
controlling of the nozzle transferring section 3 for transferring the
nozzle 2, insufficient dispensing amount of the sample Sa by the nozzle
2, or insufficient injecting amount of the diluent La by the nozzle 12 is
conceivable.

[0162]On the other hand, if the abnormality detecting section 235
determines that Ag02>Agm does not hold (step S232: No), since such a
case is where the average value Agm of the integrated values of actual
discharge pressure measurement values in the nozzle 2 is within a
reference range, it is determined that the stirring process has been
performed in a normal manner (step S236). Subsequently, the abnormality
detecting section 235 outputs a detection result (step S238), and ends
the abnormal stirring detecting process.

[0163]As described above, the stirring device 201 according to Embodiment
2 determines whether or not the stirring process has been performed in a
normal manner on liquid of a stirring subject in the container, on the
basis of the amount of deviation between the discharge pressure waveform
measured by the pressure measuring section 6 and the discharge pressure
waveform pre-obtained during normal stirring. Thereby, it becomes
possible to prevent liquid that is not stirred in a normal manner from
being used in an analyzing process, and reduce the waste of reagents and
analyzing time in the analyzing process.

[0164]In addition, the stirring device 201 determines whether or not the
integrated value of discharge pressure measurement values within the
predetermined period of time Tg of the discharge pressure waveform
measured by the pressure measuring section 6, is within the tolerance
range set on the basis of the integrated value of pressure measurement
values within the predetermined period of time Tg of discharge pressure
waveforms pre-obtained at normal stirring. In other words, the stirring
device 201 determines whether there is abnormality in the stirring
process using a value obtained by integrating timewise the amounts of
deviation from the discharge pressure waveform of normal stirring of a
discharge pressure waveform measured by the pressure measuring section 6;
and there are a plurality of pressure measurement values to be
integrated. Thereby, a more reliable determination can be made as to
whether or not there is an abnormality in the stirring process, compared
to the case where the determination is made using the amount of deviation
at only one point. In addition, in the stirring device 201, the
abnormality detecting process is performed on the basis of, not a
pressure measurement value in an unstable state, but an integrated value
of pressure measurement values during a period when the discharge
pressure waveform is stabilized. Thereby, it becomes possible to reduce
an influence of deviation in pressure measurement values in an unstable
state to perform detecting of abnormalities in a stirring process
accurately. Further, in the stirring device 201, each integrated value of
pressure measurement values is calculated for each plurality of
discharging processes and the abnormality detecting process is performed
using the average value of the plurality of integrated values, so that
there is a larger number of monitored points and measured discharge
pressure values to be averaged, compared to the case where the
determination is made using an integrated value of pressure measurement
values of only one discharging process, thereby performing a reliable
determination on whether or not there is abnormality in a stirring
process.

[0165]Further, according to Embodiment 2, it is possible to detect, not
only the existence of a simple abnormality in a stirring process, but
also a cause of the abnormality in the stirring process. Accordingly, a
maintenance worker of the stirring device 201 can recognize with which
mechanism a cause of abnormality in the stirring process is associated,
thereby handling the abnormality in the stirring process of the stirring
device quickly and accurately.

[0166]Typically, when different liquids of a stirring subject have the
same amount and viscosity, a discharge pressure waveform will be
substantially the same every time during a stirring process in a normal
manner. Therefore, the stirring device 201 may determine the existence of
abnormal stirring on the basis of each tolerance range in accordance with
each amount and viscosity of liquid to be a stirring subject. More
specifically, the stirring device 201 may perform stirring processes in
advance with different amounts and viscosities of liquid, and obtain an
integrated value of discharge pressure values within a predetermined
period of time of a discharge pressure waveform in the stirring
processes, and the stirring device 201 may set, on the basis of
respective integrated values or the like, a threshold value Ag01, which
is the upper limit of a tolerance range, and a threshold value Ag02,
which is the lower limit of a tolerance range, corresponding to each
amount and each viscosity of liquid.

[0167]In addition, according to Embodiment 2, it is also possible to
provide a threshold value corresponding to each of the insufficient
liquid amount and the nozzle 2 not reaching the liquid surface, to
determine in detail which of the insufficient liquid amount or the nozzle
2 not reaching the liquid surface has caused an abnormal stirring
process.

[0168]FIG. 15 illustrates a waveform Wg0 representing a discharge pressure
waveform of normal stirring as well as a waveform Wg21 representing a
discharge pressure waveform of abnormal stirring resulting from an
insufficient liquid amount, and a waveform Wg22 representing a discharge
pressure waveform of abnormal stirring resulting from the nozzle 2 not
reaching a liquid surface. As represented by the waveform Wg21 in FIG.
15, each discharge pressure value of an insufficient liquid amount
indicates a value with a lower negative discharge pressure compared to
the waveform Wg0 of normal stirring because the amount of discharged
liquid is less than a predetermined amount. Further, as represented by
the waveform Wg22 in FIG. 15, each discharge pressure value in the case
of the nozzle 2 not reaching a liquid surface indicates a value with a
still lower negative discharge pressure, compared to the waveform Wg21 in
the case of an insufficient liquid amount, because the liquid cannot be
discharged. As described above, a certain tendency can be recognized in a
value distribution of respective discharge pressure values in the case of
an insufficient liquid amount and the case of the nozzle 2 not reaching a
liquid surface. In the stirring device 201, this tendency is used and a
threshold value is set, which allows to distinguish the case of an
insufficient liquid amount from the case of the nozzle 2 not reaching a
liquid surface, in addition to the threshold value Ag02, which allows to
distinguish whether or not it is normal stirring, to determine which is
the cause of the abnormal stirring process, the insufficient liquid
amount or the nozzle 2 not reaching a liquid surface.

[0169]More specifically, a threshold value Ag03 may be set, which allows
to distinguish the case of the insufficient liquid amount from the case
of the nozzle 2 not reaching a liquid surface, as represented by an arrow
Y27, on the basis of an average value Ag21 of integrated values of
discharge pressure values within the predetermined period of time Tg in
the waveform Wg21 at an insufficient liquid amount represented by an
arrow Y25, and an average value Ag22 of integrated values of discharge
pressure values within the predetermined period of time Tg in the
waveform Wg22 in the case of the nozzle 2 not reaching a liquid surface
represented by an arrow Y26. abnormality detecting section 235 determines
that a stirring process has not been performed in a normal manner due to
an insufficient liquid amount in a case where an integrated value of
discharge pressure values is less than the threshold value Ag02 and is
equal to or more than the threshold value Ag03, within a predetermined
period of time Tg, during which pressure waveforms are stabilized. In
addition, the abnormality detecting section 235 determines that a
stirring process has not been performed in a normal manner due to the
nozzle 2 not reaching a liquid surface in a case where an integrated
value of discharge pressure values is less than the threshold value Ag02
and is still less than the threshold value Ag03, within a predetermined
period of time Tg, during which pressure waveforms are stabilized. As
described above, by further providing the threshold value Ag03, the
stirring device 201 may determine in detail which is the cause of an
abnormal stirring process, the insufficient liquid amount or the nozzle 2
not reaching a liquid surface.

Embodiment 3

[0170]Next, Embodiment 3 will be described. In Embodiment 3, a case will
be described for detecting abnormality in a stirring process on the basis
of both a pressure waveform at liquid suction and a pressure waveform at
liquid discharge in a stirring process.

[0171]FIG. 17 is a diagram schematically illustrating a structure of a
stirring device according to Embodiment 3. As illustrated in FIG. 17, a
stirring device 301 according to Embodiment 3 includes an abnormality
detecting section 335 instead of the abnormality detecting section 35
illustrated in FIG. 1.

[0172]The abnormality detecting section 335 determines whether or not a
stirring process has been performed in a normal manner with respect to
liquid, on the basis of the amount of deviation between a suction
pressure waveform representing a suction pressure change measured by a
pressure measuring section 6 and a suction pressure waveform pre-obtained
during normal stirring, as well as the amount of deviation between a
discharge pressure waveform representing a discharge pressure change
measured by the pressure measuring section 6 and a discharge pressure
waveform pre-obtained during normal stirring.

[0173]The abnormality detecting section 335 herein performs abnormality
detection on a stirring process, using an integrated value of suction
pressure values measured by the pressure measuring section 6, with the
range from the threshold value As01 to the threshold value As02 set in
Embodiment 1 as a first tolerance range. In addition, the abnormality
detecting section 335 performs abnormality detection on a stirring
process, using an integrated value of discharge pressure values measured
by the pressure measuring section 6, with the range from the threshold
value Ag01 to the threshold value Ag02 set in Embodiment 2 as a second
tolerance range.

[0174]The abnormality detecting section 335 determines that a stirring
process has been performed in a normal manner on liquid when an
integrated value of suction pressure measurement values within a
predetermined period of time, of a suction pressure waveform measured by
the pressure measuring section 6 is within the first tolerance range,
which is set on the basis of an integrated value of pressure measurement
values within a predetermined period of time of a suction pressure
waveform pre-obtained during normal stirring; and when an integrated
value of discharge pressure measurement values within a predetermined
period of time, of a discharge pressure waveform measured by the pressure
measuring section 6 is within the second tolerance range, which is set on
the basis of an integrated value of pressure measurement values within a
predetermined period of time of a discharge pressure waveform
pre-obtained during normal stirring. On the other hand, the abnormality
detecting section 335 determines that a stirring process has not been
performed in a normal manner on liquid when the integrated value of
suction pressure measurement values measured by the pressure measuring
section 6 has deviated out of the first tolerance, and/or the integrated
value of discharge pressure measurement values measured by the pressure
measuring section 6 has deviated out of the second tolerance.

[0175]Further, the abnormality detecting section 335 determines that the
stirring process has not been performed in a normal manner on the liquid
due to an insufficient liquid amount, the nozzle 2 not reaching a liquid
surface, the nozzle 2 being clogged, or the nozzle 2 contacting a bottom
surface of the container, in accordance with the combination of a case
when the integrated value of suction pressure measurement values measured
by the pressure measuring section 6 is more than the upper limit of the
first tolerance range or a case when the integrated value of suction
pressure measurement values measured by the pressure measuring section 6
is less than the lower limit of the first tolerance range, and a case
when the integrated value of discharge pressure measurement values
measured by the pressure measuring section 6 is more than the upper limit
of the second tolerance range or a case when the integrated value of
discharge pressure measurement values measured by the pressure measuring
section 6 is less than the lower limit of the second tolerance range.

[0176]Next, the stirring process in the stirring device 301 will be
described with reference to FIG. 18. As illustrated in FIG. 13, the
stirring device 301 performs process steps similar to the steps S1 to S9
illustrated in FIG. 5, so as to perform an undiluted solution dispensing
process (step S301), a diluent injecting process (step S302), a nozzle
lowering process (step S303), a pressure measurement starting process
(step S304), a stirring-subject liquid suction process (step S305), a
stirring-subject liquid discharging process (step S306), a pressure
measurement ending process (step S307), a stirring-subject liquid suction
process and stirring-subject liquid discharging process performed for a
set number of times determining process (step S308), and a nozzle raising
process (step S309).

[0177]Next, the abnormality detecting section 335 compares an integrated
value of pressure measurement values within suction and an integrated
value of pressure measurement values within discharge measured by the
pressure measuring section 6, with each of threshold values stored in a
storing section 36 to perform an abnormal stirring detecting process for
detecting the presence of abnormalities in the stirring process and a
cause of abnormal stirring (step S310).

[0179]Subsequently, the abnormal stirring detecting process illustrated in
FIG. 18 will be described with reference to FIG. 19. As illustrated in
FIG. 19, the abnormality detecting section 335 obtains suction pressure
data, which represents a pressure measurement value at suction (step
S322), and subsequently, obtains discharge pressure data, which
represents a pressure measurement value at discharge (step S323), among
pressure measurement values measured by the pressure measuring section 6.
Subsequently, the abnormality detecting section 335 performs a
calculating process for integrating pressure measurement values within
the predetermined period of time Ts for every set of stirring-subject
liquid discharging processes performed a set number of times to calculate
an average value Asm of the integrated values as well as integrating
pressure measurement values within the predetermined period of time Tg
for every set of stirring-subject liquid discharging processes performed
a set number of times to calculate an average value Agm of the integrated
values (step S324).

[0180]Subsequently, the abnormality detecting section 335 refers to a
determination table from the storing section 36, the determination table
representing contents of abnormality detected in a stirring process
corresponding to each combination of the average values Asm and Agm of
integrated values (step S326). The abnormality detecting section 335
obtains a detection result with respect to a stirring process,
corresponding to a combination of the Asm and Agm, which are calculation
results, by referring to the determination table (step S328), and outputs
the obtained detection result (step S338), thus ending the abnormal
stirring detecting process.

[0181]For example, as illustrated in FIG. 20, the determination table
shows combinations of the average value

[0182]Asm of integrated values in suction pressure data and the average
value Agm of integrated values in discharge pressure data, with
corresponding results of whether or not there is abnormality in a
stirring process as well as corresponding cause of abnormality; and the
determination table is stored in the storing section 36.

[0183]A case with a combination number "1" will be described. This is a
case where the average value Asm of integrated values in suction pressure
data is equal to or more than the As01 and is equal to or less than the
As02, and is within the first tolerance range, and where the average
value Agm of integrated values in discharge pressure data is equal to or
more than the Ag02 and is equal to or less than the Ag01, and is within
the second tolerance range. In such a case with the combination number
"1", the tolerance range is satisfied both in the suction and discharge,
and therefore, the abnormality detecting section 335 determines that the
subject stirring process has been performed in a normal manner.

[0184]In addition, a case with a combination number "2-2" will be
described. This is a case where the average value Asm of integrated
values in suction pressure data is equal to or more than the As01 and is
equal to or less than the As02, and is within the first tolerance range,
but where the average value Agm of integrated values in discharge
pressure data is less than the Ag02. In this case, since the average
value Agm of integrated values in discharge pressure data is less than
the threshold value Ag02 and has deviated out of the tolerance range, the
threshold value being the lower limit of the tolerance range and being a
reference for determining the occurrence of an insufficient liquid amount
or the nozzle 2 not reaching a liquid surface, it can be determined that
an insufficient liquid amount or the nozzle 2 not reaching a liquid
surface has occurred in a discharging process for stirring-subject
liquid. In such a case with the combination number "2-2" as described
above, the abnormality detecting section 335 determines that the subject
stirring process has not been performed in a normal manner due to an
insufficient liquid amount or the nozzle 2 not reaching a liquid surface
at a discharging process. In the case with the combination number "2-2",
the average value is determined as being within the tolerance range in
the suction process, and therefore, the insufficient liquid amount is
insignificant compared to a case with "4-3" to be described later.

[0185]When the average value Agm of integrated values in discharge
pressure data is more than the Ag01 herein, it is when the nozzle 2 is
clogged during a discharging process. In addition, in order for the
nozzle 2 to be in a clogged condition during a discharging process for
discharging sucked liquid, it can be said that such is a case where the
nozzle 2 was already clogged during a suction process prior to the
discharging process. Therefore, when the average value Agm of integrated
values in discharge pressure data is more than the threshold value Ag01,
it is apparent that the average value Asm of integrated values will be
less than the threshold value As01 resulting from the clogging in the
nozzle 2 during the suction process, as well. Thus, it is considered that
a case with a combination number "2-1", that is, a case where the average
value Asm of integrated values in suction pressure data is equal to or
more than the threshold value As01 and is equal to or less than the
threshold value As02 as well as the average value Agm of integrated
values in discharge pressure data is more than the threshold value Ag01,
will not occur.

[0186]Further, a case with a combination number "3-2" will be described.
This is a case where the average value Agm of integrated values in
discharge pressure data is equal to or more than the Ag02 and is equal to
or less than the Ag01 and is within the second tolerance range, but where
the average value Asm of integrated values in suction pressure data is
less than the As01. That is, this is a case where the average value Asm
of integrated values in suction pressure data is less than the threshold
value As01 and has deviated out of the tolerance range, the threshold
value being the lower limit of the tolerance range and being a reference
for determining the occurrence of clogging in the nozzle 2, but the
average value Agm of integrated values in discharge pressure data is
normal. In this case, although abnormality is recognized in the suction
process resulting from clogging in the nozzle 2, the discharging process
is performed in a normal manner. Thus, it can be considered that although
clogging occurred in the nozzle 2 immediately prior to the end of the
suction process of stirring-subject liquid, the clogging was solved at
discharge and the amount of suction is at a level with substantially no
problem. The insufficient liquid amount in the case with the combination
number "3-2" is insignificant compared to a case with "4-1" to be
described later.

[0187]When the average value Asm of integrated values in suction pressure
data is more than the As02 herein, it is when a set predetermined amount
of liquid was not sucked due to the insufficient liquid amount or the
nozzle 2 not reaching a liquid surface during a suction process. In
addition, when it is only able to suck an amount of liquid that is less
than the set amount, it means that only an amount of liquid that is less
than the set amount can be discharged at a discharging process.
Therefore, when the average value Asm of integrated values in suction
pressure data is more than the As02, it is apparent that the average
value Agm of integrated values will be less than the threshold value Ag02
resulting from an insufficient liquid amount or the nozzle 2 not reaching
a liquid surface. Thus, it is considered that a case with a combination
number "3-1", that is, a case where the average value Asm of integrated
values in suction pressure data is more than the threshold value As02 as
well as the average value Agm of integrated values in discharge pressure
data is equal to or more than the threshold value Ag02 and is equal to or
less than the threshold value Ag01, will hardly ever occur. However, when
the volume at suction is barely at the threshold value and the volume is
immeasurable, there is a possibility for such a case to be a case with
the combination number "3-1".

[0188]Next, a case with a combination number "4-1" will be described. The
case with the combination number "4-1" is when the average value Asm of
integrated values in suction pressure data is less than the threshold
value As01, which is a reference for determining the occurrence of
clogging in the nozzle 2, and the average value Agm of integrated values
in discharge pressure data is less than the threshold value Ag02, which
is a reference for determining an insufficient liquid amount or the
nozzle 2 not reaching a liquid surface. This is considered to be the case
where the amount of discharged liquid is insufficient at a discharging
process as a result that the nozzle 2 was clogged during a suction
process and thus the amount of liquid sucked was small. Thus, in the case
with the combination number "4-1", the abnormality detecting section 335
determines that the subject stirring process has not been performed in a
normal manner due to the occurrence of clogging during the suction
process.

[0189]Next, a case with a combination number "4-2" will be described. This
is a case where the average value Asm of integrated values in suction
pressure data is less than the threshold value As01, which is a reference
for determining the occurrence of clogging in the nozzle 2, and the
average value Agm of integrated values in discharge pressure data is more
than the threshold value Ag01, which is a reference for determining the
occurrence of clogging in the nozzle 2. For a case such as this, a case
can be considered where the nozzle 2 is clogged from the beginning of
suction and liquid is not sucked at all, for example, a case where the
nozzle 2 contacts a bottom surface of the stirring container 23 with
stirring-subject liquid contained therein. Thus, in the case with the
combination number "4-2", the abnormality detecting section 335
determines that the subject stirring process has not been performed in a
normal manner due to the nozzle contacting the bottom surface of the
stirring container 23. It is noted that in the case with the combination
number "4-2", there is also a possibility that the case is due to simple
clogging.

[0190]Next, a case with a combination number "4-3" will be described. This
is a case where the average value Asm of integrated values in suction
pressure data is more than the threshold value As02, which is a reference
for determining the occurrence of an insufficient liquid amount or the
nozzle 2 not reaching a liquid surface, and the average value Agm of
integrated values in discharge pressure data is less than the threshold
value Ag02, which is a reference for determining an insufficient liquid
amount or the nozzle 2 not reaching a liquid surface. This is considered
to be the case when an insufficient liquid amount or the nozzle 2 not
reaching a liquid surface has occurred both during a suction process and
during a discharging process. When it is a case with the combination
number "4-3", the abnormality detecting section 335 determines that the
subject stirring process has not been performed in a normal manner due to
an insufficient liquid amount or the nozzle 2 not reaching a liquid
surface both during a suction process and during a discharging process.
The case with the combination number "4-3" means a completely
insufficient liquid amount.

[0191]As previously described, it is apparent that the nozzle 2 was
already clogged at a suction process when the average value Agm of
integrated values in discharge pressure data is more than the Ag01 and
the nozzle 2 is clogged at a discharging process. Accordingly, it is
apparent that when the average value Agm of integrated values in
discharge pressure data is more than the threshold value Ag01, the
average value Asm of integrated values will be less than the threshold
value As01 due to clogging in the nozzle 2, during a suction process, as
well. Thus, it is considered that the case with a combination number
"4-4", that is, the case where the average value Asm of integrated values
in suction pressure data is more than the threshold value As02, which is
a reference for determining the occurrence of an insufficient liquid
amount or the nozzle 2 not reaching a liquid surface, and the average
value Agm of integrated values in discharge pressure data is more than
the threshold value Ag01, will not occur.

[0192]As described above, the stirring device 301 according to Embodiment
3 uses both of the suction pressure waveform and the discharge pressure
waveform measured by the pressure measuring section 6, so that it becomes
possible to detect the presence of an abnormality in a stirring process
more reliably and detect a cause of the abnormality in the stirring
process in detail, compared to a case where either one of the suction
pressure waveform or the discharge pressure waveform is used.

[0193]In addition, in the stirring devices 1, 201 and 301 according to
Embodiments 1 to 3, the rate of upward and downward driving by the piston
4b may be set so that pressure measurement can be reliably performed by
the pressure measuring section 6. In the dispensing device, the rate of
upward and downward driving by the piston therein is precisely controlled
so that a predetermined amount of liquid can be dispensed accurately. On
the contrary, it is enough for the stirring devices 1, 201 and 301 to be
able to stir liquid sufficiently, and therefore, high dispensing accuracy
is not particularly required of the stirring devices 1, 201 and 301.
Therefore, in the stirring devices 1, 201 and 301, in order to obtain
many pressure measurement points by the pressure measuring section 6, the
upward and downward driving rate by the piston 4b maybe adjusted in
accordance with the pressure measurement timing by the pressure measuring
section 6. For example, the upward and downward driving rate can be
slowed down than the upward and downward driving rate by the piston in
the dispensing device by referring to the measurement timing of the
pressure measuring section 6. As a result, it becomes possible to detect
abnormal stirring in the stirring devices 1, 201 and 301 with certain
accuracy.

[0194]In addition, in the stirring devices 1, 201 and 301 according to
Embodiments 1 to 3, abnormality is detected in a stirring process on the
basis of a pressure value applied to the nozzle 2, and abnormality can be
detected in a stirring process as long as there is an enough amount of
stirring-subject liquid for pressure measurement. Therefore,
abnormalities can be detected sufficiently in a stirring process with
respect to a small amount of stirring-subject liquid. In addition, in the
stirring devices 1, 201 and 301 according to Embodiments 1 to 3, an
abnormality is detected in a stirring process using a pressure value
applied to the nozzle 2. Therefore, abnormalities can be detected in a
stirring process of stirring-subject liquid without the stirring-subject
liquid having particular characteristics, such as conductivity.

[0195]The stirring devices 1, 201 and 301 according to Embodiments 1 to 3
can be applied as a stirring device in an analyzer for analyzing a
sample, such as blood and urine. In this case, the stirring devices 1,
201 and 301 is applied as a stirring device for diluting a sample, such
as blood and urine, with a predetermined diluent. More specifically, an
analyzer which is applied with the stirring device 1 will be described,
among the stirring devices 1, 201 and 301.

[0197]The sample rack conveying section 411 conveys a sample rack 413
arranged in a rack feeder 4111, under the control of a controlling
section 404 to be described later. The sample rack 413 is loaded with a
plurality of containers 22, which contain samples (specimens), and the
sample rack conveying section 411 successively transfers the sample rack
413 to convey the containers 22 to a predetermined sample suction
position.

[0198]In the meantime, at a predetermined diluent dispense position, a
predetermined amount of a diluent is dispensed into each of stirring
containers 23 in a diluted sample rack 419 by the diluent dispensing
section 421 including a plurality of nozzles 12 for discharging a
diluent. The stirring containers 23 which are dispensed with the diluent
are transferred to a predetermined sample discharge position.

[0199]The sample dispensing section 415 includes a nozzle 2 for sucking
and discharging a sample. Under the control of the controlling section
404, the sample dispensing section 415 performs dispensing by sucking the
sample in the container 22 by the nozzle 2, the container 22 being
transferred to the sample suction position, and successively discharging
the sucked sample into each of the stirring containers 23 at the
predetermined sample discharge position. Subsequently, through a suction
process and a discharging process, the dispensed sample and the diluent
are stirred.

[0200]The diluted sample dispensing section 423 includes a plurality of
sample nozzles for performing suction and discharge of a diluted sample.
Under the control of the controlling section 404, the diluted sample
dispensing section 423 sucks a diluted sample by each sample nozzle from
each of the stirring containers 23 in the diluted sample rack 419
transferred to a diluted sample suction position, and transfers the
diluted sample to a diluted sample discharge position. A microplate 427
is placed at the diluted sample discharge position, the microplate 427
being constituted of a plurality of reaction containers 4271, referred to
as a well, arranged in a matrix thereon. The diluted sample dispensing
section 423 performs dispensing by discharging each diluted sample into
each of the reaction containers 4271 of the microplate 427.

[0201]In order to dispense the diluted sample and a reagent into each of
the reaction containers 4271 of the microplate 427 and measure mixed
liquid of the diluted sample and the reagent in each of the reaction
containers 4271, under the control of the controlling section 404, the
plate conveying section 425 transfers the microplate 427 at the diluted
sample discharge position and conveys the reaction containers 4271 to a
reagent discharge position, and subsequently conveys them to a
measurement position. A reagent is dispensed by a reagent dispensing
section 429 into the reaction containers 4271 conveyed to the reagent
discharge position.

[0202]The reagent dispensing section 429 includes reagent nozzles, each of
which performs suction and discharge of a reagent. Under the control of
the controlling section 404, the reagent dispensing section 429 sucks a
reagent in each of reagent containers 4311 of a reagent storing section
431 by each reagent nozzle, and transfers the reagent to a reagent
discharge position. Subsequently, the reagent dispensing section 429
discharges the reagent into the reaction containers 4271 conveyed by the
plate conveying section 425 to the reagent discharge position. The
reagent storing section 431 stores a plurality of reagent containers 4311
arranged therein, each of which contains a predetermined reagent that
causes an antigen-antibody reaction with a sample.

[0203]The microplate 427 is conveyed to the measurement position by the
plate conveying section 425 after the diluted sample is dispensed into
the reaction containers 4271 by the diluted sample dispensing section
423, a reagent is dispensed into the reaction containers 4271 by the
reagent dispensing section 429, and an antigen-antibody reaction is
completed with the sample in the reaction containers 4271 with the elapse
of a necessary reaction time. By the antigen-antibody reaction, an
aggregation reaction pattern is formed at a bottom surface of each of the
reaction containers 4271.

[0204]The measuring section 433 includes: an image capturing section 4331,
such as a CCD camera, provided above a measurement position, for
capturing from above an image of a microplate 427 conveyed to the
measurement position; and a light source 4333 provided below the
measurement position, for radiating irradiation light on reaction
containers 4271 of the microplate 427. The image capturing section 4331
receives light that has passed through the reaction containers 4271 to
capture an image of an aggregation reaction pattern formed on the bottom
surface each of the reaction containers 4271. The obtained measurement
result (image information) is output to the controlling section 404.
Typically, with regard to a positive sample, aggregation takes place with
a sample and a reagent; and with regard to a negative sample, aggregation
does not take place with a sample and a reagent.

[0205]The plate collecting section 435 collects a microplate 427 which has
ended with measurement by the measuring section 433. The collected
microplate 427 is cleaned in a cleaning section (not shown) to be
re-used. More specifically, mixed liquid in the reaction containers 4271
is discharged, and cleaning is performed by discharge and suction of
cleaning liquid, such as a detergent or cleaning water. There is a case
where the microplate 427 is thrown away after completion of one
measurement depending on the content of testing.

[0206]In addition, the analyzer 401 includes a controlling section 404 for
controlling sections which constitute the analyzer by instructing
operational timings, transferring data and the like to the sections to
control operation of the overall analyzer comprehensively. The
controlling section 404 is constituted of a microcomputer or the like,
which includes a memory built therein for storing, in addition to an
analysis result, various data necessary for the operation of the analyzer
401, and the controlling section 404 is placed at an appropriate position
in the analyzer 401. The controlling section 404 is connected with an
analyzing section 441 and outputs a measurement result by the measuring
section 433 to the analyzing section 441. The analyzing section 441
analyzes an antigen-antibody reaction on the basis of a measurement
result by the measuring section 433, and outputs an analysis result to
the controlling section 404. For example, the analyzing section 441
performs image processing on image information obtained by the measuring
section 433 to detect and judge an aggregation reaction pattern formed on
each bottom surface of reaction containers 4271. In addition, the
controlling section 404 is connected with an input section 443
constituted of an input device, such as a keyboard and a mouse, for
inputting information necessary for analysis, such as the number of
samples and analysis items; and an output section 445 constituted of a
display device and the like, such as an LCD and an ELD, for displaying an
analysis result screen, a warning screen, an input screen for inputting
various settings and the like. In addition, similar to the stirring
device 1 illustrated in FIG. 1, the analyzer 401 includes: an abnormality
detecting section 35 for detecting abnormality in a stirring process in
the diluent dispensing section 421; and a storing section 436 for storing
various information used for an abnormality detecting process by the
abnormality detecting section 35.

[0207]As described above, the analyzer 401 includes the stirring device 1,
201 or 301 according to Embodiments 1 to 3, thereby preventing a sample
and a diluent which are not stirred in a normal manner from being used in
an analyzing process to improve analysis accuracy.

[0208]The stirring devices 1, 201 and 301 and the analyzer 401 described
in the above embodiments can be achieved by executing a prepared program
in a computer system. The computer system achieves processing operation
of the analyzer by reading and executing a program recorded in a
predetermined recording medium. Herein, the predetermined recording
medium can be any recording medium for recording a program readable by a
computer system, including a "portable medium", such as a flexible disk
(FD), a CD-ROM, an MO disk, a DVD disk, a magneto-optical disk and an IC
card, as well as a "communication medium" for storing a program for a
short period of time in transmitting the program, such as a hard disk
drive (HDD) provided either inside or outside the computer system. In
addition, the computer system achieves processing operation of the
stirring device and analyzer by obtaining a program from a management
server or other computer system connected via a network line and
executing the obtained program.

INDUSTRIAL APPLICABILITY

[0209]As described above, the stirring device and analyzer according to
the present invention is suitable for correctly detecting abnormalities
in a stirring process and preventing liquid which has not been stirred in
a normal manner from being used in an analyzing process.